Microquasars as heating sources of the intergalactic medium during reionisation of the Universe

TL;DR

This paper investigates how high-redshift microquasars' jets accelerate electrons that significantly heat and partially ionize the intergalactic medium during reionisation, comparable to cosmic rays from supernovae.

Contribution

It introduces Monte Carlo simulations to model electron propagation from microquasars and assesses their impact on the intergalactic medium during reionisation.

Findings

Microquasars significantly heat the intergalactic medium.

They are effective ionisers near galaxies.

Their heating effect is comparable to cosmic rays from supernovae.

Abstract

The effect of the primeval sources of radiation and particles on the thermodynamical state of the intergalactic medium during the Epoch of Reionisation is still unclear. In this work, we explore the contribution of electrons accelerated in the jets of high-redshift microquasars to heating and ionising the intergalactic medium. We develop Monte Carlo simulations of the propagation and energy deposition of these electrons as they travel away from their sources. We find that microquasars contribute significantly to heating the intergalactic medium and are effective ionisers only near the galaxies. Their effect on heating is of the same order of magnitude than that of CRs from SNe.